The present invention relates to a pallet for transporting an armature between processing stations of an armature manufacturing line, before incorporation of the armature in a dynamoelectric machine such as an electric motor. In particular, this invention relates to such a pallet which can handle the armature in more than one state, as the state of the armature is altered during manufacture.
An armature of a dynamoelectric machine has a length defined by its shaft, which ordinarily does not change during manufacturing. It is therefore common to support an armature on a pallet, which moves the armature from station to station of a manufacturing line, by supporting the ends of the armature shaft. At any particular processing station of the manufacturing line, the armature may be processed while it is still supported on the pallet. Alternatively, the armature may be removed from the pallet by equipment at the processing station, processed, and returned to the pallet.
However, characteristics of the armature other than length may change during manufacture. For example, while the shaft ends normally have fixed diameters, at certain stages during manufacture the diameter of a shaft end may be temporarily increased. In particular, when a commutator is being placed on the shaft, there are steps during which the commutator remains at the end of the shaft, effectively increasing the shaft diameter at that end. The supports on the pallet, which are designed to handle the unincreased shaft diameter, cannot hold the shaft during that time.
It is known to provide pallets that can be adjusted to accommodate armatures of different lengths. Such pallets are shown, for example, in commonly-assigned U.S. Pat. Nos. 5,060,780, 5,060,781, 5,099,978, 5,115,901, 5,255,778, 5,346,058 and 5,474,166. Similarly, pallets that can be adjusted to accommodate stators of different sizes are shown, for example, in commonly-assigned U.S. Pat. Nos. 4,965,924, 5,065,499, 5,240,235 and 5,373,623. However, such pallets are adjusted once for a particular armature or stator configuration at the beginning of the manufacture of that armature or stator.
It would be desirable to be able to provide an armature pallet that can accommodate an armature as the configuration of the armature changes through different steps of the armature manufacturing process.